The Boston police bomb squad investigated an incident Thursday in which a passenger dropped a suspicious object under an MBTA bus in the Longwood medical area. But it turned out that the object was a plastic chocolate milk bottle.

The incident was reported at 9:26 a.m. when a passenger on a Route 66 bus got off near Brigham Circle and dropped the bottle under the vehicle, Joe Pesaturo, MBTA spokesman, said in e-mail. The driver contacted public safety officials.

Boston and Transit Police cleared the scene near the intersections of Tremont Street and Huntington Avenue to investigate the object, officials said. The bottle was deemed unsuspicious, and the scene was cleared around 10:45 a.m.

The passenger who dropped the bottle was taken into custody and will be charged with disorderly conduct and interfering with public transportation, Pesaturo said.